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The Pelican Ionization Front

Distance: 1,800 light-years away from Earth

The light from young energetic stars is slowly transforming the Pelican’s cold gas to hot gas, with the advancing boundary between the two known as an ionization front. Most of these bright stars lie off the top of the image, but part of the bright ionization front crosses on the upper right. Particularly dense and intricate filaments of cold gas are visible along the front. Millions of years from now this nebula might no longer be known as the Pelican, as the balance and placement of stars and gas will leave something that appears completely different.

Credit: John Bally (U. Colorado) & Bo Reipurth (U. Hawaii), NOAO, AURA, NSF